Field of the Invention
The present invention is related to a microscope provided with a plurality of optical units for autofocus (hereafter referred to as AF), observation, light stimulus, etc., each including a filter block.
Description of the Related Art
In the field of biomicroscopes, there is a well known microscope having various functions including not only the function of illuminating and observing a cultivated sample, but also the function of stimulating the cultivated sample with light and the AF function of correcting an out-of-focus image to observe the cultivated sample for a long time.
The various functions are realized by providing between an objective and a tube lens an optical unit for light stimulus to introduce stimulus light to the optical axis and for AF to introduce autofocus light to the optical axis of an objective in addition to an optical unit for a fluorescent observation conventionally provided to introduce excitation light to the optical axis of an objective.
The microscope provided with a plurality of optical units between an objective and a tube lens is disclosed by, for example, Japanese Laid-open Patent Publication No. 2006-091723. The microscope disclosed by Japanese Laid-open Patent Publication No. 2006-091723 is an inverted microscope provided between an objective and a tube lens with an optical unit including a dichroic mirror for introducing light from a lamplight source, and an optical unit including a dichroic mirror for introducing laser light from a laser.
With the microscope provided with an infinity-corrected objective, on-axis light is emitted as luminous flux parallel to an optical axis from an objective to a tube lens while off-axis light is emitted as parallel flux inclined with respect to the optical axis from the objective to the tube lens.